Many invasive medical procedures that previously required major surgery are now performed using endoscopic instruments. Such instruments can provide an internal view of particular body parts, organs, or passages without requiring invasive surgery. Generally, an endoscopic instrument may include one or more channels through which miniaturized, flexible instruments can be inserted and advanced. The endoscope typically includes an elongated flexible cable equipped at one end with an eyepiece or other viewing means and at the other end with an optical head. Only the head is directly and externally connected to the instrument. The cable transmits images or image-producing signals from the illuminated operative site to the viewing means to provide the instrument operator with full vision of the actions being performed at the instrument's working end. A coherent optic bundle extends from the head and through the flexible cable through the eyepiece for providing the surgeon with visual confirmation of the instrument's tip or jaw action. The illuminating means may take the form a light-transmitting waveguide extending through the cable to illuminate the operative area. The waveguide is connected at its proximal end to a suitable high-intensity light source.
The cable of an endoscope also provides a flow passage for the delivery of fluid (e.g., liquid or gas) for irrigation or other purposes. Typically, the flow passage and the illuminating means are disposed on opposite sides of the coherent image-transmitting waveguide. In conventional practice, it is necessary to provide a flow of sterile water across the optic head to prevent the buildup of materials (e.g., surgical debris and body fluids) on the optic head. This flow of water operates, in a sense, like a windshield wiper/washer assembly.
In common designs, an endoscopic instrument typically has a control body which is connected by a light guide tube to a light guide connector, which actually can include a plurality of connectors that can suitably receive various fittings. For example, the light guide connector can include a connector orifice that receives a grounding lug, a suction port, an air inlet, and a water inlet. As such, the air and water are delivered through the light guide connector, through the light guide tube and into the control body. Alternatively, the control body can also include a water port so as to allow water to be directly provided to the control body. Suitable valves are provided on the control body so as to control the flow of water through the control body and over the optic head of the instrument.
For example, FIG. 1 illustrates an endoscope system that is unmodified (i.e., includes no secondary gas supply means). The endoscope is shown to include a shaft (insertion tube) connected to a control body that includes a biopsy port, air-water and suction valves, and angulation controls. The control body is connected to an umbilical (light guide connecting tube) that further connects to an electrical pin unit, which is directly connected to a light source and is connected via a video connection lead (and plug) to a video processor. The image produced by the endoscope is transmitted via a fiber optic bundle, or electronically from a charge-coupled device (CCD) chip. FIG. 1 illustrates a video monitor and attached keyboard for viewing images and inputting commands. The electrical pin unit includes a port for a water bottle connector that connects to a water bottle for providing irrigation.
The somewhat complex internal anatomy of the endoscope is further illustrated in FIG. 2, which shows a detailed view of the endoscope from FIG. 1. As seen in FIG. 2, the shaft incorporates an instrumentation channel extending from the entry biopsy port to the tip of the instrument. Channel sizes can vary from about 1 to 5 mm. Again, the endoscope includes no means for a secondary gas supply.
Unexpectedly, there is usually a great expense associated with the delivery of sterile water in an endoscopy system. As seen in FIG. 1, the known practice has been to use a water bottle with a cap having a tube running therethrough. The tube typically has a fitting at the end distal to the bottle to allow for connection to the air/water connection port of the light guide connector (of the electrical pin unit, as illustrated in FIG. 1) or to the port on the endoscope control body. Typically, the tube connecting the water bottle to the endoscope is formed of an inner tube and an outer tube. The outer tube extends into the water bottle and is connected to the cap of the water bottle. In normal practice, air is delivered through the area between the inner tube and the outer tube so as to pressurize the interior of the water bottle and force water to flow through the tube and into the endoscope at a desired rate.
The known water bottle configuration presents several problems. First is the issue of cost and sterilization. For example, the guide accompanying one known endoscope device includes the following instructions:                Failure to properly clean and high-level disinfect endoscopic equipment after each examination can compromise patient safety.        Every channel of the endoscope must be reprocessed each time the endoscope is used, even if the channel was not utilized during the preceding patient procedure.        Every channel must go through every reprocessing step (cleaning, disinfection, rinsing, alcohol-air drying).In practice, after usage, the water bottle, its associated tubing, and its associated fittings are sterilized, such as by glutaraldehyde disinfection and/or autoclaving. This creates a considerable expense to the hospital including the considerable labor expense associated with the disinfection of the water bottle. There is also the possibility of residual contaminants residing in the area of connection between the tubes and the bottle. It also has not typically been feasible to simply dispose of a water bottle after a single use because of the expense associated with the water bottle/cap/tubing systems.        
Another issue with known water bottles is the gas source. Ambient air is often pumped into the system to charge the water bottle, as described above. It can be desirable, however, to use a secondary gas source instead of ambient air. Known devices allowing for substitution with a secondary gas source are excessively expensive and can still suffer the problems associated with disinfection after each use. The present invention beneficially provides a solution to these and other problems associated with known water bottles for use in endoscopy systems.